Conventional household hand mixers have an array of mechanical switches for speed selection. When a selected speed switch is engaged, the hand mixer operates at the selected speed until the operator pushes an off switch that mechanically disengages the speed switch. Some conventional hand mixers already have feedback systems. However, the speed stability and speed accuracy is not satisfactory, especially when the hand mixer runs at a low speed and under a heavy loading condition. This makes the mixing result inconsistent and sometimes causes the motor to burn due to the heating efficiency positive feedback. Some conventional hand mixers already have a count up timer feature. All conventional electronic hand mixers have a manual power off feature. However, no one have an auto shut off feature.
Some aspects of conventional hand mixers have safety hazard. For example, a conventional hand mixer that is not equipped with a timer will continue to run if left unattended, especially when using the hand mixer as a stand mixer.
If a conventional hand mixer is used to do a complicated mixing course, which combines several stages with different speed associated with different time, the user has to control the mixing time for each stage manually. In addition, the user must rely on his or her memory and/or visual observation of the results to make a successful mixing cycle.